This part is a kind of semiconductor called 31DQ04.

Function of this product has SCHOTTKY RECTIFIER.

Manufacturers : International Rectifier

Image and pinout :

Some of the text within the PDF file :

Bulletin PD-2.304 rev. E 03/03 31DQ03 31DQ04 SCHOTTKY RECTIFIER 3.3 Amp Major Ratings and Characteristics Characteristics IF(AV) Rectangular waveform VRRM IFSM @ tp = 5 µs sine VF TJ @ 3 Apk, TJ = 25°C Description/Features Units A V A V °C The 31DQ.. axial leaded Schottky rectifier has been optimized for very low forward voltage drop, with moderate leakage. Typical applications are in switching power supplies, converters, free-wheeling diodes, and reverse battery protection. Low profile, axial leaded outline High purity, high temperature epoxy encapsulation for enhanced mechanical strength and moisture resistance Very low forward voltage drop High frequency operation Guard ring for enhanced ruggedness and long term reliability 31DQ.. 3.3 30/40 450 0.57 - 40 to 150 CASE STYLE AND DI [ ... ]

31DQ04 PDF Datasheet Download